Dear Maintainer,

The Dell Venue 11 Pro 7139 has a dock (Dell K10a (proprietary)) that is used to
provide additional I/O to the device. Most of that functionality works out of
the box under linux, with the exception of the dock's ethernet port. (A ASIX
AX88179 USB 3.0 Gigabit Ethernet chipset embedded in the dock itself.)

That port only works if the Venue is booted without being connected to the dock
during POST / initial kernel start. Otherwise linux will fail to detect the
dock's ethernet port at all, (no dmesg output at all), despite everything else
on the dock working. No amount of unplugging and replugging in the dock will
fix it. (Even unplugging the dock from it's own separate power source does
nothing to resolve the issue.) In this case the only solution is a full
shutdown and reboot. (With the dock disconnected from the Venue during the
reboot.)

This puts a lot of repetitive strain on the dock's spring loaded connector as
it means that everytime linux reboots, the Venue must be removed from the dock
and then reattached for the ethernet port to continue working.

No amount of tweaking settings in the Venue's BIOS / firmware seems to fix it.
(Fastboot disabled, UEFI Secure boot disabled, Disable Legacy ROMs, etc.) And
there is no option in the BIOS / firmware to disable network booting entirely.
The BIOS / Firmware just seems to be putting the USB NIC into an unknown state
that linux can't recover from, if it detects the card during POST. A state that
is unique to the dock NIC itself. Plugging in a different USB ethernet device
(even one with a similar chipset) works as expected even if that different non-
dock NIC is connected during POST.

I've attached some dmesg output from both a boot with the dock connected and
without (and what booting without looks like after linux is booted and the dock
attached.)

Hi Patrick

As I understand your description this is *not* a regression from a
previously working 6.1.y version correct?

You could test please newer kernel versions either from backports or
directly from trixie/unstable and can you report back if those fix the
problem?

Regards,
Salvatore

Hi Salvatore
Yes, to my knowledge it's never worked correctly, and I've not seen anyone else report the issue.
Testing with the current trixie kernel it's still broken, with the same behavior as the original bug report.

I've attached the updated kernel dmesg outputs.

The "reconnection" logs are the dmesg output after the dock is unplugged from the machine, and then reconnected.
Only the disconnected_at_boot log shows the NIC being detected.